docker-images: publish sourcegraph/opentelemetry-collector with bundled config

Created by: bobheadxi

This new image also bundles some default configuration files that can be used to export traces to Jaeger or Honeycomb - see the new image README for more details.

Test plan

This is a main dry run that will build a candidate image. This PR also includes a test of Honeycomb export, which is super easy, and which you can set up in sg.config.overwrite.yaml:

commands:
  otel-collector:
    env:
      CONFIGURATION_FILE: 'configs/honeycomb.yaml'
      HONEYCOMB_API_KEY: '🕵️'

The "link to trace" needs some work though (currently just breaks)